Doohan will race for Alpine in the Abu Dhabi Grand Prix in place of Esteban Ocon this weekend.
Ocon has been released from Alpine ahead of the final race of the year freeing him to join Haas, for whom he’ll race next season, at the post-season test in Yas Marina next week.
That has in turn created an opening on the grid, with Doohan given the nod to make his first F1 race start ahead of schedule as a result.
The accelerated debut comes as Alpine finds itself in a constructors’ championship battle with Haas for sixth in the standings.
For now, the Anglo-French operation holds the upper hand and is odds on to retain the place regardless.
Doohan will become the 24th different driver to have competed in F1 this season, following the likes of Oliver Bearman and Franco Colapinto.
The Australian was set to be part of a bevy of rookies for 2025 that included Kimi Antonelli, Gabriel Bortoleto, while Bearman will also join the championship full-time with Haas following this two cameos this year.
Bearman substituted for Carlos Sainz in Saudi Arabia where he scored points on debut, before joining Haas for Azerbaijan when Kevin Magnussen was banned.
He made a solid account for himself in both outings, suggesting the step from F2 to F1 was not as great as many thought.
However, Antonelli had a far less auspicious start when he crashed just minutes into his F1 career when he spun out of Free Practice 1 at the Italian Grand Prix when he stepped into George Russell’s car.
“I think anyone who gets thrown into an F1 car in a race like that, it’s never easy to judge,” Alpine team boss Oli Oakes said when Speedcafe asked what expectations he had of Doohan in Abu Dhabi.
“The problem is, you’ve got the benchmark Bearman set, which was phenomenal in Saudi.
“You’ve got, and I mean this in a nice way because he’s hugely talented, but you had Kimi with the sort of pressure in Monza.
“At the end of the day, Jack’s just got to take it as he finds it.
“He’s professional enough to handle it.
“I think as well, once you ease into the weekend, FP1, FP2, you can build up to it as well.”
That’s an approach Piastri went a good way to trademarking through his rookie season; starting slowly and only showing his true pace when it mattered in qualifying.
It was a deliberate act, designed to maximise track time which in turn expedited his ability to gain experience.
While Doohan’s not raced since stepping out of F2 at the end of last year in Abu Dhabi, he’s been remaining sharp.
There’s been a healthy number of private test sessions with Alpine, across both older and current spec machinery and he completed Free Practice 1 duties at the Canadian and British Grands Prix this season too.
“The program has been, dare I say, well planned for him,” Oakes said of Doohan’s program as a reserve driver.
“Although the team doesn’t get much credit from the Piastri situation, they are obviously pretty good with young drivers and preparing them.
“Jack’s been on that same path.
“He’s been with me quite a bit in the garage, he listens to intercom with me, and [Flavio Briatore], giving us his two pennies as well.
“I’m sure he’s ready for it.”
Track action for the Abu Dhabi Grand Prix begins on Friday with opening practice from 13:30 local time (20:30 AEDT).